CVE-2023-53746 s390/vfio-ap: fix memory leak in vfio_ap device driver
A memory leak in the s390/vfio-ap Linux kernel driver allows local attackers to exhaust system memory, causing denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-53746?
CVE-2023-53746 is a memory corruption vulnerability in Linux, published on 8 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
s390/vfio-ap: fix memory leak in vfio_ap device driver
The device release callback function invoked to release the matrix device uses the dev_get_drvdata(device *dev) function to retrieve the pointer to the vfio_matrix_dev object in order to free its storage. The problem is, this object is not stored as drvdata with the device; since the kfree function will accept a NULL pointer, the memory for the vfio_matrix_dev object is never freed.
Since the device being released is contained within the vfio_matrix_dev object, the container_of macro will be used to retrieve its pointer.
Which versions are affected by CVE-2023-53746?
How do I fix CVE-2023-53746?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2023-53746 being exploited?
There is no known exploitation of CVE-2023-53746 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-53746, DEBIAN-CVE-2023-53746, GHSA-pfq8-pr42-5qc2, UBUNTU-CVE-2023-53746.